26 lines
No EOL
1.4 KiB
Text
26 lines
No EOL
1.4 KiB
Text
\--- Day 4: The Ideal Stocking Stuffer ---
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Santa needs help [mining](https://en.wikipedia.org/wiki/Bitcoin#Mining) some AdventCoins (very similar to [bitcoins](https://en.wikipedia.org/wiki/Bitcoin)) to use as gifts for all the economically forward-thinking little girls and boys.
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To do this, he needs to find [MD5](https://en.wikipedia.org/wiki/MD5) hashes which, in [hexadecimal](https://en.wikipedia.org/wiki/Hexadecimal), start with at least *five zeroes*. The input to the MD5 hash is some secret key (your puzzle input, given below) followed by a number in decimal. To mine AdventCoins, you must find Santa the lowest positive number (no leading zeroes: `1`, `2`, `3`, ...) that produces such a hash.
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For example:
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* If your secret key is `abcdef`, the answer is `609043`, because the MD5 hash of `abcdef609043` starts with five zeroes (`000001dbbfa...`), and it is the lowest such number to do so.
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* If your secret key is `pqrstuv`, the lowest number it combines with to make an MD5 hash starting with five zeroes is `1048970`; that is, the MD5 hash of `pqrstuv1048970` looks like `000006136ef...`.
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Your puzzle answer was `254575`.
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\--- Part Two ---
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Now find one that starts with *six zeroes*.
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Your puzzle answer was `1038736`.
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Both parts of this puzzle are complete! They provide two gold stars: \*\*
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At this point, all that is left is for you to [admire your Advent calendar](/2015).
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Your puzzle input was `bgvyzdsv`. |